redirecting webpages

I realize this may be the wrong spot to post this, but how do I redirect a web browser to a different webpage. I want to have anyone that uses my wifi network to be redirected to my webpage, 'blank.com' whenever they type in any other url. How would I do that? Is is something with my router? I wanted to start a 'internet cafe', where users must first log in or pay before using the net. Thanks